An explosion at a fuel depot in Azerbaijan’s Nagorno-Karabak has killed 20 people and injured hundreds more

The explosion comes as the Armenian government said 13,350 refugees had crossed into the country from the enclave. The disputed Nagorno-Karabak region is home to a majority of some 120,000 ethnic Armenians.

It is not yet clear what caused the explosion on Monday evening in the main city of Stepanakert.

In a statement on Tuesday local officials said 13 unidentified bodies were found at the scene and seven more had died in hospital.

Since Azerbaijan’s seizure of Nagorno-Karabak last week, thousands of people have left the area after the Armenian government in Yerevan announced plans to move those made homeless by the fighting.